What a GK3 pickup is and why you might install one
The GK3 is a hexaphonic pickup made by Roland that sits on top of your guitar's existing pickups. Instead of reading all six strings as one signal, it sends a separate signal from each string to a processor or synthesizer. This lets you trigger drum sounds, synth voices, or effects on individual strings while still playing a normal guitar.
You install it because you want to use guitar-to-MIDI conversion, play synthesizer sounds triggered by your guitar, or run each string through different effects. The pickup itself mounts to the guitar body with a bracket, and the cable runs to a GK-3m interface box or directly into a compatible amplifier or processor.
Installation takes about 30 minutes if you are comfortable with a screwdriver and routing a cable. You do not need to modify the guitar permanently — the pickup and bracket can be removed without damage.
Key Takeaways
- The GK3 mounts to your guitar body with a bracket and sits just above the bridge pickup, held in place by two screws.
- You route the 13-pin cable from the pickup down through the guitar body or along the strap, then to a GK-3m interface box or compatible device.
- The pickup needs to sit at the correct height — roughly 2 to 3 mm from the strings — so adjustment after mounting is normal.
- The GK3 works alongside your regular pickups, so your amp still receives a normal guitar signal unless you use a separate output.
What you need before you start
Gather a Phillips head screwdriver, the GK3 pickup kit (which includes the pickup unit, mounting bracket, and 13-pin cable), and the GK-3m interface box if you are using one. You will also want a small ruler or caliper to measure the distance between the pickup and your strings.
Check that your guitar has enough clearance under the bridge. Acoustic guitars, archtop guitars, and some semi-hollow bodies may not have room for the bracket. Solid-body electrics — Stratocasters, Telecasters, Les Pauls, and similar — work without issue.
If your guitar has a tremolo arm or a floating bridge, test that the pickup bracket will not interfere with the bridge movement before you tighten anything down.
Mounting the bracket and pickup to your guitar
Position the mounting bracket on your guitar body so that the pickup will sit directly above the bridge pickup, roughly centered over the strings. On most guitars, this means the bracket sits about 1 to 2 inches behind the bridge. Mark the two screw holes with a pencil.
Drill pilot holes at those marks using a drill bit slightly smaller than the mounting screws — this prevents the wood from splitting. If your guitar is a high-end instrument and you are uncomfortable drilling, a luthier can do this step for you. Screw the bracket down firmly but do not over-tighten, which can crack the wood or strip the threads.
Slide the GK3 pickup unit into the bracket from the side and secure it with the locking screw. The pickup should sit level and parallel to the strings. Do not tighten the locking screw all the way yet — you will adjust the height after you string the guitar back up.
Routing the cable and connecting to your interface
The 13-pin cable exits the pickup unit and needs to reach your interface box or amplifier. On solid-body guitars, you can route the cable down through the body cavity if your guitar has a control cavity or electronics access point. Drill a small hole (about 3/8 inch) in the body if one does not already exist, or use an existing hole for a strap button.
On guitars without easy internal routing, run the cable along the back of the body and down the strap. Use small adhesive cable clips to keep it tidy and prevent it from moving around while you play. Leave enough slack at the output end so the cable does not pull on the pickup if you move the guitar.
Connect the 13-pin connector to the GK-3m interface box. The GK-3m has a power supply, a USB output for MIDI, and audio outputs for the hexaphonic signal. Plug in the power supply and connect the USB to your computer or the audio outputs to your amplifier or effects processor, depending on how you want to use it.
Adjusting the pickup height and testing
String your guitar back up and tune it to pitch. Measure the distance between the top of the GK3 pickup and the bottom of each string. The ideal distance is 2 to 3 mm — close enough to pick up the string vibration clearly, but far enough away that the strings do not hit the pickup when you play hard.
Loosen the locking screw on the bracket slightly and adjust the pickup up or down until the distance is even across all six strings. Tighten the locking screw again. If the pickup is too close, the strings will buzz against it; if it is too far, the signal will be weak or intermittent.
Play each string individually and listen for a clear, consistent signal in your interface or amplifier. If one string is much quieter than the others, the pickup may be tilted — loosen the bracket and adjust it so the pickup sits parallel to the strings again.
Connecting to your device and software
If you are using the GK-3m interface, plug the USB cable into your computer. Most DAWs and music software recognize the GK-3m as a MIDI input device automatically. In your software's MIDI settings, select the GK-3m as your input source.
If you are using the audio outputs, connect them to your amplifier, mixer, or effects processor. The GK3 sends six separate audio channels — one per string — so you can route each string to a different effect or synthesizer if your equipment supports it.
Test by playing a single string and confirming that your software or device receives the signal. Adjust the sensitivity in your software if the signal is too quiet or too loud. Most GK3 software has a per-string gain control so you can balance the output from all six strings.
Troubleshooting common problems
If the pickup produces no signal, check that the 13-pin connector is fully seated in the interface box and that the power supply is plugged in. Verify that your software or device recognizes the GK-3m as an input. If the cable is routed inside the guitar body, it may have come loose — open the electronics cavity and reseat the connector.
If the signal is weak or intermittent, the pickup is probably too far from the strings. Lower it by loosening the bracket screw and sliding the pickup down, then re-measure the distance. If one or two strings are much quieter than the others, the pickup may be tilted — adjust the bracket until the pickup is parallel to the strings.
If the strings buzz against the pickup, it is too close. Raise it by loosening the bracket and sliding it up. The ideal distance is 2 to 3 mm, but you may need to go slightly higher if you play with a heavy touch.
Frequently Asked Questions
Can I use a GK3 on an acoustic guitar?
Not easily. Acoustic guitars have a curved top and a floating bridge, so there is no flat surface to mount the bracket. Some players have mounted a GK3 on the pickguard of an acoustic, but it requires custom fabrication and may interfere with normal playing. A piezo pickup or magnetic soundhole pickup is a better choice for acoustics.
Does the GK3 replace my regular pickups?
No. The GK3 sits above your bridge pickup and sends a separate signal to your interface or processor. Your regular pickups still work normally and send their signal to your amplifier. You can use both at the same time or blend between them depending on your setup.
What if I want to remove the GK3 later?
Unscrew the bracket from the guitar body and remove the pickup. The two screw holes will remain visible, but you can fill them with wooden toothpicks and wood glue if you want to restore the guitar to its original state. The guitar will not be damaged by the installation.
Do I need a GK-3m interface, or can I connect the GK3 directly to my amp?
The GK3 cable is a 13-pin connector that does not fit standard guitar amplifiers. You need either a GK-3m interface box (which converts the signal to USB MIDI and audio outputs) or a compatible amplifier or processor that has a 13-pin input — some Roland amplifiers and Kemper profilers have this. Check your equipment before you buy the GK3.
How much does a GK3 installation cost if I take it to a luthier?
A luthier typically charges between $50 and $150 for the installation, depending on whether drilling is needed and how much cable routing is required. If your guitar needs internal routing through the body cavity, the cost may be higher. Call ahead and ask for an estimate based on your specific guitar.